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grep(1) User Commands grep(1)
NAME
grep - search a file for a pattern
SYNOPSIS/usr/bin/grep [-bchilnsvw] limited-regular-expression [filename...]
/usr/xpg4/bin/grep [-E | -F] [-c | -l | -q] [-bhinsvwx] -epat-tern_list... [-fpattern_file]... [file...]
/usr/xpg4/bin/grep [-E | -F] [-c | -l | -q] [-bhinsvwx] [-epat-tern_list...] -fpattern_file... [file...]
/usr/xpg4/bin/grep [-E | -F] [-c | -l | -q] [-bhinsvwx] pattern
[file...]
DESCRIPTION
The grep utility searches text files for a pattern and prints all lines
that contain that pattern. It uses a compact non-deterministic algo-
rithm.
Be careful using the characters $, *, [, ^, |, (, ), and \ in the pat-tern_list because they are also meaningful to the shell. It is safest
to enclose the entire pattern_list in single quotes '... '.
If no files are specified, grep assumes standard input. Normally, each
line found is copied to standard output. The file name is printed
before each line found if there is more than one input file.
/usr/bin/grep
The /usr/bin/grep utility uses limited regular expressions like those
described on the regexp(5) manual page to match the patterns.
/usr/xpg4/bin/grep
The options -E and -F affect the way /usr/xpg4/bin/grep interprets pat-tern_list. If -E is specified, /usr/xpg4/bin/grep interprets pat-tern_list as a full regular expression (see -E for description). If -F
is specified, grep interprets pattern_list as a fixed string. If nei-
ther are specified, grep interprets pattern_list as a basic regular
expression as described on regex(5) manual page.
OPTIONS
The following options are supported for both /usr/bin/grep and
/usr/xpg4/bin/grep:
-b Precede each line by the block number on which it was found. This
can be useful in locating block numbers by context (first block
is 0).
-c Print only a count of the lines that contain the pattern.
-h Prevents the name of the file containing the matching line from
being appended to that line. Used when searching multiple files.
-i Ignore upper/lower case distinction during comparisons.
-l Print only the names of files with matching lines, separated by
NEWLINE characters. Does not repeat the names of files when the
pattern is found more than once.
-n Precede each line by its line number in the file (first line is
1).
-s Suppress error messages about nonexistent or unreadable files.
-v Print all lines except those that contain the pattern.
-w Search for the expression as a word as if surrounded by \< and
\>.
/usr/xpg4/bin/grep
The following options are supported for /usr/xpg4/bin/grep only:
-epattern_list
Specify one or more patterns to be used during the search for
input. Patterns in pattern_list must be separated by a NEWLINE
character. A null pattern can be specified by two adjacent new-
line characters in pattern_list. Unless the -E or -F option is
also specified, each pattern will be treated as a basic regular
expression. Multiple -e and -f options are accepted by grep. All
of the specified patterns are used when matching lines, but the
order of evaluation is unspecified.
-E Match using full regular expressions. Treat each pattern speci-
fied as a full regular expression. If any entire full regular
expression pattern matches an input line, the line will be
matched. A null full regular expression matches every line. Each
pattern will be interpreted as a full regular expression as
described on the regex(5) manual page, except for \( and \), and
including:
1. A full regular expression followed by + that matches one or
more occurrences of the full regular expression.
2. A full regular expression followed by ? that matches 0 or 1
occurrences of the full regular expression.
3. Full regular expressions separated by | or by a new-line that
match strings that are matched by any of the expressions.
4. A full regular expression that may be enclosed in parentheses
() for grouping.
The order of precedence of operators is [], then *?+, then con-
catenation, then | and new-line.
-fpattern_file
Read one or more patterns from the file named by the path name
pattern_file. Patterns in pattern_file are terminated by a NEW-
LINE character. A null pattern can be specified by an empty line
in pattern_file. Unless the -E or -F option is also specified,
each pattern will be treated as a basic regular expression.
-F Match using fixed strings. Treat each pattern specified as a
string instead of a regular expression. If an input line contains
any of the patterns as a contiguous sequence of bytes, the line
will be matched. A null string matches every line. See fgrep(1)
for more information.
-q Quiet. Do not write anything to the standard output, regardless
of matching lines. Exit with zero status if an input line is
selected.
-x Consider only input lines that use all characters in the line to
match an entire fixed string or regular expression to be matching
lines.
OPERANDS
The following operands are supported:
file A path name of a file to be searched for the patterns. If no file
operands are specified, the standard input will be used.
/usr/bin/greppattern
Specify a pattern to be used during the search for input.
/usr/xpg4/bin/greppattern
Specify one or more patterns to be used during the search for
input. This operand is treated as if it were specified as -epat-tern_list.
USAGE
The -epattern_list option has the same effect as the pattern_list oper-
and, but is useful when pattern_list begins with the hyphen delimiter.
It is also useful when it is more convenient to provide multiple pat-
terns as separate arguments.
Multiple -e and -f options are accepted and grep will use all of the
patterns it is given while matching input text lines. (Note that the
order of evaluation is not specified. If an implementation finds a null
string as a pattern, it is allowed to use that pattern first, matching
every line, and effectively ignore any other patterns.)
The -q option provides a means of easily determining whether or not a
pattern (or string) exists in a group of files. When searching several
files, it provides a performance improvement (because it can quit as
soon as it finds the first match) and requires less care by the user in
choosing the set of files to supply as arguments (because it will exit
zero if it finds a match even if grep detected an access or read error
on earlier file operands).
LargeFileBehavior
See largefile(5) for the description of the behavior of grep when
encountering files greater than or equal to 2 Gbyte ( 2**31 bytes).
EXAMPLESExample1:Findingallusesofaword
To find all uses of the word "Posix" (in any case) in the file text.mm,
and write with line numbers:
example% /usr/bin/grep-i-nposixtext.mmExample2:Findingallemptylines
To find all empty lines in the standard input:
example% /usr/bin/grep^$
or
example% /usr/bin/grep-v .
Example3:Findinglinescontainingstrings
Both of the following commands print all lines containing strings abc
or def or both:
example% /usr/xpg4/bin/grep-E 'abc def'
example% /usr/xpg4/bin/grep-F 'abc def'
Example4:Findinglineswithmatchingstrings
Both of the following commands print all lines matching exactly abc or
def:
example% /usr/xpg4/bin/grep-E '^abc$ ^def$'
example% /usr/xpg4/bin/grep-F -x 'abc def'
ENVIRONMENT VARIABLES
See environ(5) for descriptions of the following environment variables
that affect the execution of grep: LC_COLLATE, LC_CTYPE, LC_MESSAGES,
and NLSPATH.
EXIT STATUS
The following exit values are returned:
0 One or more matches were found.
1 No matches were found.
2 Syntax errors or inaccessible files (even if matches were found).
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
/usr/bin/grep
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
|CSI |enabled |
+-----------------------------+-----------------------------+
/usr/xpg4/bin/grep
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWxcu4 |
+-----------------------------+-----------------------------+
|CSI |enabled |
+-----------------------------+-----------------------------+
SEE ALSOegrep(1), fgrep(1), sed(1), sh(1), attributes(5), environ(5), large-file(5), regex(5), regexp(5), XPG4(5)NOTES/usr/bin/grep
Lines are limited only by the size of the available virtual memory. If
there is a line with embedded nulls, grep will only match up to the
first null; if it matches, it will print the entire line.
/usr/xpg4/bin/grep
The results are unspecified if input files contain lines longer than
LINE_MAX bytes or contain binary data. LINE_MAX is defined in
/usr/include/limits.h.
SunOS 5.9 20 Oct 1997 grep(1)